Social class and asthma--distinguishing between the disease and the diagnosis

Framing disease: an underappreciated mechanism for the social patterning of health

The emerging fields of social epidemiology and population health seek to understand the social determinants of health. Especially, with regards to how income inequality causes health disparities, attention has been focused on material and psychosocial mechanisms. I use examples from the epidemiological and social science literature to argue for a third broad etiological framework: the role played by the ways we generally recognize, define, name, and categorize disease states and attribute them to a cause or set of causes. These framing effects shape population health by influencing: health and illness beliefs; patterns of consumption and other behaviors; perceptions of what interventions and policies work; class, ethnic, and other social dynamics; and clinical and public health practices. Important characteristics of many framing phenomena are their capacity to be self-perpetuating and their performative power. A better understanding of framing effects can lead to deploying them more deliberatively and flexibly to improve individual and population health.

Asthma burden in a citywide, diverse sample of elementary schoolchildren in Chicago

OBJECTIVE

The purposes of this study are to describe and develop preliminary models of the burden of diagnosed asthma and symptoms of possible undiagnosed asthma in a large, citywide, ethnically and socioeconomically diverse sample of Chicago elementary schoolchildren. We hypothesized that considering possible asthma would give a more complete picture of race/ethnic disparities in pediatric asthma.

METHODS

We studied 35,583 students aged 6 to 12 years attending Chicago Public and Archdiocese elementary schools for the Chicago Initiative to Raise Asthma Health Equity (CHIRAH) study. The full enrollments of 105 schools were surveyed for asthma and possible undiagnosed asthma by the Brief Pediatric Asthma Screen Plus (BPAS+) respiratory symptoms. The child had to be 6 to 12 years old, the valid age range for the BPAS+. Questionnaires included the BPAS+, basic demographic information, and household asthma information; they were sent home with each schoolchild for completion by the parent and returned to school for collection and scoring.

RESULTS

Overall, 13.9% of students had diagnosed asthma. For children aged 6 to 12 years, rates of diagnosed asthma varied from 13.1% to 14.5%, whereas the rates of possible undiagnosed asthma varied from 14.8% to 10.9%. The rate of diagnosed asthma was 21.2% for African Americans, 9.7% for whites, 11.8% for Hispanics, with similar rates of possible undiagnosed asthma. By multinomial logistic regression, African Americans were more than twice as likely and Hispanics were 1.57 times more likely than whites to have diagnosed asthma at all school district income levels and controlling for other household members with asthma, type of school, age of the child, gender, and language preference. The odds of African Americans being diagnosed with asthma rather than having possible asthma were 76% higher and for Hispanics were 46% higher compared with whites, at all school district income levels and controlling for other household members with asthma, type of school, age of the child, gender, and language preference.

CONCLUSIONS

Our study confirms national disparities in diagnosed asthma by race/ethnicity. Respiratory symptoms consistent with possible undiagnosed asthma increase the total potential burden of asthma overall to more than one-quarter of the school enrollees. Among students with respiratory symptoms, African Americans, Hispanics (controlling for language), and families where another person has asthma are more likely to have diagnosed rather than possible asthma. Improved knowledge about asthma, recognition of symptoms, and access to high-quality care are necessary to ascertain how much of the possible undiagnosed asthma represents additional cases of asthma requiring treatment.

Asthma hospitalizations among American Indian and Alaska Native people and for the general US population

STUDY OBJECTIVES

Asthma is one of the most common chronic diseases in the United States. High rates of asthma hospitalization have been reported for some ethnic minorities; however, asthma hospitalization rates for American Indian/Alaska Native (AI/AN) populations of all ages have not been studied. In this study, we examined and compared hospitalization rates for AI/AN populations and the general population in the United States.

DESIGN

Hospital discharge records with a first-listed diagnosis of asthma were evaluated for AI/AN populations and the US general population of all ages from 1988 to 2002.

RESULTS

The asthma hospitalization rate for AI/AN populations decreased from 17.8/10,000 per year in 1988 to 1990 to 12.9/10,000 per year in 2000 to 2002. The overall age-adjusted rate for 2000 to 2002 was slightly lower than that for the general US population (12.9/10,000 and 16.4/10,000, respectively). However, AI/AN populations living in the Southwest region (17.6/10,000) had the highest asthma hospitalization rate among the Indian Health Service regions and the rate from 2000 to 2002 was similar to that for the general US population. The 2000 to 2002 asthma hospitalization rate for AI/AN populations < 1 year of age (infants) was higher than that in US infants, and the rates for AI/AN age groups > or = 1 year were similar to or lower than those for the general US population.

CONCLUSIONS

While asthma was rarely reported among AI/AN populations before 1975, the average annual age-adjusted asthma hospitalization rate was only slightly lower for AI/AN populations than that for the US general population from 2000 to 2002. Furthermore, the asthma hospitalization rates for AI/AN populations living in the Southwest and East regions were similar to the rate for the general US population. Efforts to further increase asthma awareness and symptom recognition among AI/AN populations should be implemented to help to reduce asthma hospitalizations.

Indoor environment and respiratory symptoms in children living in the Dutch-German borderland

OBJECTIVE

To investigate the relation between indoor environmental risk factors and respiratory symptoms in 7-8-year-old children living in the Dutch-German borderland.

METHODS

A nested case-control study was conducted among children participating in a large longitudinal study on respiratory health. Parents of all 781 children with respiratory complaints and an equal number of randomly selected controls were asked to complete a questionnaire, including questions on indoor environment.

RESULTS

The parents of 1191 children (76.2%) participated. Past exposure to environmental (OR = 2.73, 95% CI 1.14-6.67) as well as in utero exposure (OR = 2.28, 95% CI 1.15-4.53) to tobacco smoke, use of an unvented geyser for water heating (OR = 3.01, 95% CI 1.21-7.56), long-term exposure to dampness (OR = 2.98, 95% CI 1.10-8.28) or pets (OR = 2.18, 95% CI 1.39-3.42) increased the risk of asthmatic symptoms in 7-8-year-old children. A middle or low socio-economic status also increased the risk of asthmatic symptoms. An inverse association with asthmatic symptoms was seen for wall-to-wall carpeting (OR = 0.57, 95% CI 0.33-0.95) and insulation measures (OR = 0.46, 95% CI 0.25-0.83). Except for the presence of an unvented geyser, these environmental risk factors also presented a risk for coughing symptoms in children.

CONCLUSION

This study showed an increased risk of respiratory symptoms in children exposed to several indoor environmental risk factors.

Racial and ethnic differences in asthma diagnosis among children who wheeze

BACKGROUND

Racial and ethnic disparities exist in reported childhood asthma prevalence, but it is unclear if disparities stem from true prevalence differences or a different likelihood of receiving a diagnosis from a health professional. Concern has been raised that asthma may be underdiagnosed, particularly among minority children who have more restricted access to high-quality health care.

OBJECTIVE

To examine racial/ethnic differences among currently symptomatic children in acquiring an asthma diagnosis to determine if relative underdiagnosis among minorities exists. Children for whom no symptoms were reported (a group that includes those with well-controlled symptoms) were excluded from the analysis.

METHODS

The 1999 National Health Interview Survey includes a nationally representative sample of children with reported wheezing symptoms. We included children 3 to 17 years old in the study and analyzed racial/ethnic differences in asthma diagnosis, controlling for young age, gender, parental education, single-parent household, central-city residence, region of residence, health insurance, having a usual place of care, and parent-reported severity of wheezing symptoms.

RESULTS

Among those reported to have wheezed in the past year (n = 946), 83% of Puerto Rican, 71% of non-Hispanic black, and 65% of Mexican children were diagnosed with asthma compared with 57% of non-Hispanic white children. Using non-Hispanic white children as the reference group, the approximate adjusted relative risk for physician diagnosis of asthma given wheezing in the past year was 1.43 (95% confidence interval [CI]: 1.04, 1.63) for Puerto Rican, 1.22 (95% CI: 1.03, 1.37) for non-Hispanic black, and 1.19 (95% CI: 0.94, 1.39) for Mexican children. Minority children were reported to have greater severity of wheezing symptoms. Even after accounting for this increased severity, children in racial and ethnic minority groups were as or more likely to have a reported asthma diagnosis than non-Hispanic white children.

CONCLUSIONS

Our findings do not provide evidence for the hypothesis that symptomatic minority children are underdiagnosed with asthma compared with non-Hispanic white children. To the contrary, among currently symptomatic children, minority children were more likely to be diagnosed than non-Hispanic white children even after accounting for the higher wheezing severity among minority children.

Comorbidity of asthma and anxiety and depression in Puerto Rican children

Studies have reported that childhood asthma is associated with internalizing disorders, but most of these studies have used global measures of depressive and anxiety symptoms. The Diagnostic Interview Schedule for Children was administered to a group of 1891 youth ages 4 to 17 and their caregivers in Puerto Rico to determine DSM-IV symptoms and diagnoses. Asthma diagnosis and having had an asthma attack were assessed by parental report. A diagnosis of asthma was associated with having any depressive disorder and one symptom of separation anxiety. An asthma attack was associated with any depressive disorder and any anxiety disorder and, more specifically, with separation anxiety disorder, major depressive disorder, and symptoms of depression, separation anxiety, and generalized anxiety. Possible explanations for the findings are discussed.

Issues in identifying asthma and estimating prevalence in an urban school population

This article first presents salient issues related to identifying children in urban schools who might benefit from asthma services. It discusses a brief questionnaire for identifying cases and problems in estimating asthma prevalence. Subsequently, results of case detection in 14 urban schools are presented and discussed in light of these issues. The questionnaire was employed with parents of 4,653 African-American children in Detroit. Results suggest that determining number, type, and frequency of symptoms may be necessary to ascertain prevalence of asthma. Using only number and type produced a rate of asthma of 25%. Adding frequency provided a more conservative estimate of 19%. About 9% of children exhibiting symptoms of asthma had no physician diagnosis. Only 25% with symptoms reflecting mild persistent, 35% with moderate persistent, and 26% with severe persistent disease had prescriptions for anti-inflammatory medicine. Further, 23% of children with asthma-like symptoms had no prescription for asthma medicine of any type.

CONCLUSIONS

(1) low-cost procedures can be used in schools to identify children with suspected undiagnosed and undertreated asthma; (2) prevalence estimates for asthma in the group of urban school children studied are among the highest in the United States; and (3) asthma is undertreated in this sample.

Racial and ethnic disparities in childhood asthma diagnosis: the role of clinical findings

OBJECTIVES

To establish rates of childhood asthma symptoms, diagnosis, and hospitalization by race, ethnicity, and income, and to ascertain if elevated reported prevalence of asthma diagnosis among African-American children could be explained by differences in clinical findings.

METHODS

Estimates of each indicator were calculated based on data from the third National Health and Nutrition and Examination Survey (NHANES III). Bivariate and multivariate logistic regression models were estimated to predict parent or guardian report of current asthma diagnosis.

RESULTS

African-American children aged 1 to 5 have a 2-fold higher probability of both asthma diagnosis and hospitalization during the previous year but no significant difference in wheeze prevalence compared to Mexican-American and European-American children. These differences are not explained by household income or clinical information. Children aged 6 to 16 had similar rates of diagnosis and hospitalization for all racial/ethnic groups, although African-American children reported wheeze symptoms one-third less often.

CONCLUSIONS

Although younger African-American children have higher morbidity from asthma than their Mexican-American and European-American peers, clinical findings were similar and did not explain increased rates of diagnosis. Interpersonal dynamics within families and communication between families and clinicians are believed to influence both symptom reporting and diagnosis generation.

Impact of site of care, race, and Hispanic ethnicity on medication use for childhood asthma

OBJECTIVE

To understand the importance of source of care and other factors that influence differences in asthma medication use by race and Hispanic ethnicity.

METHODS

The Childhood Asthma Severity Study provided 12-month, retrospective, parent-reported questionnaire data on a monthly basis for children ages </=12 years in a community sample of 1002 children and their families from Connecticut and Massachusetts. Medications considered included cromolyn, beta2-agonist, inhaled steroids, anticholinergics, theophylline, and systemic steroids. Information was available on demographics, insurance status, symptom severity, primary care contact, and provider practice types.

RESULTS

Black and Hispanic children received fewer beta2-agonists, and Hispanic children received fewer inhaled steroids than white children after adjusting for patients' race, age, gender, insurance status, symptom severity, number of primary care visits for asthma, number of urgent visits to the regular provider, family income, maternal education, and site of care. When multivariate analyses were restricted to patients in private practice, the significant association between Hispanic ethnicity and low inhaled steroid use persisted, whereas differences in beta2-agonist use by race and ethnicity changed little but became nonsignificant.

CONCLUSION

Even within private practices, patients' race and ethnicity are associated with clinician nonadherence to national guidelines. Programs to eliminate these disparities will need both to focus on site of care and to intervene at the provider and patient levels to be successful.

Differences in asthma prevalence between samples of American Indian and Alaska Native children

OBJECTIVES

To better understand the prevalence of asthma among American Indian and Alaska Native (AI/AN) children and to explore the contribution of locale to asthma symptoms and diagnostic assignment, the authors surveyed AI/AN middle school students, comparing responses from metropolitan Tacoma, Washington (metro WA) and a non-metropolitan area of Alaska (non-metro AK).

METHODS

Students in grades 6-9 completed an asthma screening survey. The authors compared self-reported rates of asthma symptoms, asthma diagnoses, and health care utilization for 147 children ages 11-16 self-reporting as AI/AN in metro WA and 365 in non-metro AK.

RESULTS

The prevalences of self-reported asthma symptoms were similar for the metro WA and non-metro AK populations, but a significantly higher percentage of metro WA than of non-metro AK respondents reported having received a physician diagnosis of asthma (OR 2.33; 95% CI 1.23, 4.39). The percentages of respondents who reported having visited a medical provider for asthma-like symptoms in the previous year did not differ.

CONCLUSIONS

The difference in rates of asthma diagnosis despite similar rates of asthma symptoms and respiratory-related medical visits may reflect differences in respiratory disease patterns, diagnostic labeling practices, or environmental factors. Future attempts to describe asthma prevalence should consider the potential contribution of non-biologic factors such as diagnostic practices.

The relation of socioeconomic factors and racial/ethnic differences in US asthma mortality

OBJECTIVES

This study described relations between socioeconomic factors and race/ethnicity as risk factors for asthma mortality.

METHODS

A cross-sectional study was conducted of US mortality records from 1991 through 1996.

RESULTS

Higher standardized mortality ratios were seen for Blacks vs Whites (3.34 vs 0.65), low vs high educational level (1.51 vs 0.69), and low vs high income (1.46 vs 0.71). Excess mortality for Blacks vs Whites was present in the highest and lowest quintiles of median county income and educational level. The disparity in asthma mortality rates according to median county income and education remained after control for race/ethnicity.

CONCLUSIONS

Black race/ethnicity appears to be associated, independently from low income and low education, with an elevated risk for asthma mortality.

Risk factors for pediatric asthma. Contributions of poverty, race, and urban residence

The Child Health Supplement to the 1988 National Health Interview Survey was used to examine parent-reported current asthma among a nationally representative sample of 17,110 children zero to 17 yr of age. Numerous demographic variables were analyzed for independent associations with asthma using modified stepwise logistic regression, with models including specific combinations of risk factors. Black children had higher rates of asthma than did white children in unadjusted analyses, but after controlling for multiple factors, black race was not a significant correlate of asthma (adjusted odds ratio = 0.87, 95% CI = 0.63 to 1.21). Compared with nonurban white children, urban children, both black and white, were at significantly increased risk of asthma: urban and black (adjusted OR = 1.45, 95% CI = 1.14 to 1.86), urban and white (adjusted OR = 1.22, 95% CI = 1.01 to 1.48), whereas nonurban black children were not: nonurban and black (adjusted OR = 1.15, 95% CI = 0.83 to 1.61). Similarly, compared with nonurban, nonpoor children, urban and poor (adjusted OR = 1.44, 95% CI = 1.05 to 1.95), urban and nonpoor (adjusted OR = 1.22, 95% CI = 1.004 to 1.48), urban children, both poor and nonpoor, were at significantly increased risk of asthma, whereas nonurban poor children were not: nonurban and poor (adjusted OR = 1.03, 95% CI = 0.72 to 1.48). These results suggest that the higher prevalence of asthma among black children is not due to race or to low income per se, and that all children living in an urban setting are at increased risk for asthma.

Asthma. The states' challenge

At the national level, asthma is increasingly being recognized as an important public health problem. Because of the significant role of environmental exposure in asthma morbidity, public health agencies have a critical role to play in the surveillance and prevention of the disease. In April 1996, the Council of State and Territorial Epidemiologists, with assistance from the Centers for Disease Control and Prevention, surveyed state and territorial public health departments to determine the status of their asthma surveillance and intervention programs. Of the 51 health departments that responded, only eight reported that they had implemented an asthma control program within the previous 10 years. Reasons cited for not having programs included lack of funds, shortage of personnel, and asthma not being a priority. Most states were unable to assess the burden of asthma because they lack data or face barriers to using existing data. Removing barriers to the use of data is a first step toward defining the scope of the asthma problem.